The government has myriad tools at its disposal to persuade or compel construction companies to up their energy efficiency game. And with a target to make all homes zero carbon by 2016 and all buildings by 2019, regulatory control of the industry is only going to get more demanding.

Already in force

Part L of the Building Regulations
The approved documents were published at the end of April and require a 25% reduction in carbon emissions compared to the 2006 version. This applies across the board for dwellings but will, for the first time, vary for non-domestic buildings according to building type. The so-called “aggregate approach” recognises that it is more cost effective to reduce carbon emissions from some types of buildings than others.

The reductions are: hotel 16%, retail 21%, shallow-plan building (heated) 22%, supermarkets 26%, deep-plan office (airconditioned) 26%, school 27%, warehouse 36% and shallow-plan office (airconditioned) 40%.

The regulations also require designers to put forward a design stage carbon dioxide emission rate and building specification to help building control understand the compliance strategy. The idea is that this will help compliance rates because building control will be able to see any changes in the finished building compared to the original specification.

For homes, designers will use a new version of SAP. Complying with Part L 2010 is going to be even tougher for housebuilders than the 25% target suggests as party walls are now assumed to have a U-value of zero. Previously, housebuilders could insulate party walls and claim carbon reductions, but now they will have to insulate these without gaining any credits. Meeting Part L 2010 will be equivalent to the energy component of level three of the Code for Sustainable Homes.

Conservatories under 30m2 remain exempt from Part L, providing the main home heating system isn’t extended into the conservatory and it is separated from the main house by a wall, window or door.

The service compliance guides for domestic and non-domestic buildings and the specification for SAP have been published. At the time of going to press the new national calculation methodology and updated version of SBEM were due to be released.

The 2010 version of Part L takes effect from 1 October, although buildings that received planning permission before this date will be able to comply with the 2006 version of Part L if they start on site before October 2011.

Part F of the Building Regulations

This covers ventilation and has been updated with Part L as airtightness rules in Part L could affect indoor air quality. The changes mainly affect homes. Homes that are more airtight than 5m3/m2/hr at 50pa will require higher ventilation rates to compensate. There are new rules on commissioning, and airflow rates for all buildings must be established and submitted to the building control body. Information on ventilation systems must now be given to home occupiers.

Code for sustainable Homes

This is the tool used by government to make all new homes zero carbon by 2016. It has six increasingly demanding levels: the base is equivalent to current Building Regulations for energy and water use with level six a zero-carbon home generating all its power with minimal water consumption. The Code also includes minimum standards for the management of surface water, site waste and household waste and the use of materials.

The road map to zero carbon is clearly set out, with progressively higher levels of the code becoming base Building Regulations in the future. So Part L 2010 will require carbon emissions to be 25% lower, equivalent to code level three, the 2013 version 44% lower and equivalent to level four and 2016 zero carbon and equivalent to
level six.

Social housing providers must already build homes to level three to receive government grants and all new homes have to be assessed against the code. Because Part L 2010 will make the energy element of levels one to three redundant, the code will be revised from October this year. See below for details.

Energy certification of buildings

All buildings need to be assessed for energy efficiency before being sold or rented. The energy performance of the building fabric is assessed and given an energy rating on an A to G scale with A being the best.

Buildings over 1,000m2 that are occupied by public bodies and those where large numbers of the public visit, such as universities, need to display a certificate showing how much energy is actually being used. This is called a display energy certificate and is based on the size of energy bills.

There are also compulsory, five-yearly energy efficiency checks for air conditioning systems. All systems with an output of over 250kW should already have been inspected by a qualified assessor, and those with an output over 12kW must be checked by January 2011.

Part G of the Building Regulations

This covers sanitation, hot water safety and water efficiency and took effect in April. For the first time there is a limit of 125 litres of water per person per day, the minimum provision in the Code for Sustainable Homes. It also defines where non-drinkable water can be used in homes and sets outs rules on water storage to make installing rainwater and greywater systems easier. Thermostatic valves and mixer taps are now required for baths to mitigate the risk of children being scalded by hot water.

The Carbon Reduction Commitment

The CRC took effect from April and affects medium-sized organisations such as developers, central and local government, healthcare trusts and supermarkets.

These organisations must record their emissions and buy carbon credits each April to cover them. Each October a carbon emissions league table is published and the money used to buy the credits is redistributed. Companies are ranked on the absolute percentage change since the previous year, good energy management during the three-year introductory phase and percentage change relative to turnover. Organisations performing better than average will get a rebate while those below will be penalised.

Companies will have to start buying carbon credits from April 2011 based on reported emissions during 2010. The financial impact will be relatively light to begin with as the carbon price is fixed at £12/tonne, but this will increase to an anticipated £40 to £50 in 2013.

However, publication of the league table is likely to prove a powerful driver for improvements.

All other building regulations

The Future of Building Control Implementation Plan sets out when the different building regulations will be revised. This happens at regular, fixed interviews. Parts L and F get revised every three years and all other regulations are revised every six years. In 2010, Parts G, F, J and L are revised. In 2013, Part L will be revised again along with Parts A, C, E, K, M, N, P and Regulation Seven. The new Part J of the regulations covers heat-producing appliances and takes effect from 1 October.

It includes biomass appliances in the rules for solid and liquid biofuel appliances and there are more generous ventilation requirements in rooms with combustion appliances for homes with an airtightness less than 5m3/m2/hr at 50pa. There is also a requirement to fit carbon monoxide detectors when a new or replacement solid fuel appliance is installed.

Coming up

Code for sustainable homes

The code is being revised to take account of the changes to Part L and the proposed new approach to the definition of zero carbon. The energy requirements for code levels one to three will be brought into line with Part L 2010, a 25% improvement over the 2006 version. Meeting these levels means hitting targets for water use, materials, water runoff and biodiversity.

The higher code energy targets stay the same, but may incorporate the proposed definition of zero carbon. This means hitting the minimum building fabric standards in the definition, and the carbon compliance targets, which equate to a 70% cut in emissions compared to Part L 2006, which must be met on site. The definition allows 30% of emissions to be met using off-site solutions, the so-called “allowable solutions.” This means 30% of the emissions from levels five and six homes will be allowed from off-site sources.

The consultation on the revision also asks whether an intermediate level for building fabric standards should be introduced in 2013 to start bringing the code into line with the definition of zero carbon before 2016.

There are other tweaks: achieving level four won’t require conforming to Lifetime Homes standards until 2013 at the earliest rather than the originally proposed 2010; site waste management plans will no longer be part of the code as these are a mandatory requirement anyway; and there are changes to the waste and cycle storage requirements. The consultation has now closed and, in theory, the new code will be published in the summer in time for implementation this October.

Definition of zero carbon

The new definition appears to be coming out in dribs and drabs. The communities department carried out a consultation that closed in March 2008 where it moved away from insisting on all energy being provided by on-site renewables. Instead, it proposed a hierarchy (see above on the Code for Sustainable Homes) where building fabric would have to meet minimum standards for energy efficiency, then on-site renewables (carbon compliance) would be used to mitigate carbon emissions further and finally off-site solutions would be allowed (allowable solutions).

In July last year housing minister John Healey announced that fabric energy efficiency and carbon compliance solutions would have to reduce carbon emissions by 70% compared to 2006, with the balance coming from allowable solutions. In November, Healey announced the energy efficiency standards for homes, based on recommendations from the Zero Carbon Hub. These consist of minimum U-values for building elements and energy use of 46kWhr/m2/yr for semi-detached and detached properties and 39kWhr/m2/yr for all other homes. These standards are consulted on in a second consultation tacked on to the end of that on revisions to the Code for Sustainable Homes.

Everyone is waiting to see what the allowable solutions will be. The consultation suggests that exports of heat to other developments, investments in low or zero-carbon community heat infrastructure and energy-efficient appliances may feature as a consultation.

Zero carbon for new non-domestic

This consultation is the first stage in moving toward the government’s target of making all buildings zero carbon by 2019. It differs from the Code for Sustainable Homes as it only tackles energy and ignores factors such as water use and impact of materials. It also recognises it is far harder to provide zero-carbon energy for all equipment in non-domestic buildings than homes. All energy for appliances in homes is covered by the code but this consultation proposes that between 10 and 20% of energy for equipment in non-domestic buildings is met from zero-carbon sources. The consultation also proposes the hierarchy set out in the definition of zero-carbon for meeting the targets:
energy-efficient fabric, then onsite low and zero-carbon technologies, so-called carbon compliance and finally “allowable” offsite solutions.

Because non-domestic buildings vary so much, there are different targets for different building types, 11 in total, an approach seen for the first time with Part L. 2010. So the consultation proposes that fabric efficiency should contribute towards a 10% cut in carbon emissions for supermarkets but 55% for a distribution warehouse.

Emissions reductions from the carbon compliance part of the hierarchy are more complicated. Again there are different targets depending on building type but three different scenarios are proposed. The first allows more energy to come from off-site sources, the second is split half and half and the third allows less energy to come from off-site solutions. Like the code, it proposes that these should be introduced in phases from 2013.

The first scenario proposes an average reduction in carbon emissions from the carbon compliance element of the hierarchy of 30% in 2013, 47% in 2016 and 44% in 2019. For the third scenario, the figures are 44% in 2013, 53% in 2016 and 63% in 2019. Because achieving this isn’t going to be easy, the government would like the public sector to lead the way. It also currently wants to see allowable solutions in place by 2016.

However, these policies were formed under the last government and some changes to energy and construction policy must be anticipated from the new regime.

The consultation closed in February and the government said it would respond some time this year. Expect to see this take effect with the 2013 revision of Part L.

Energy performance of buildings

This is the Europe-wide instrument that gave us energy and display performance certificates. It is being revised to extend its scope and clarify and simplify existing provisions. Proposals include extending the scope of display energy certificates so they must be provided for all buildings occupied by a public authority or frequently visited by the public that are over 250m2
There are also proposals for energy performance certificates (EPCs) to be displayed in all commercial premises over 500m2 that are frequently visited by the public rather than the current 1,000m2, and to make it compulsory to include EPC ratings in property advertisements.

The original proposal to require all existing buildings, rather than only those over 1,000m2, to improve energy performance when upgraded has been modified and can now be applied only to those elements that are upgraded, which is already a requirement of Part L. The directive is expected to take effect from the end of 2012.